The Accelerator Pedal Position (APP) Sensor is a Linear Potentiometer that monitors the accelerator pedal position. The APP Sensor operates within a 5 volt DC reference range, and provides a linear input signal to the Powertrain Control Module (PCM). The PCM uses data from the APP Sensor to calculate air-fuel mixture, ignition timing, fuel injector pulse width, and transmission/transaxle gear position.
Removal & Installation
- Before servicing the vehicle, refer to the precautions.
- Unplug the connector.
- Remove the cover over the accelerator pedal position sensor and detach the connector from the cover.
- Unhook the accelerator cable from the cam disc.
Remove the accelerator pedal position sensor.
- Installation is the reverse of removal.
Accelerator Pedal Position Sensor
A properly operating APP Sensor should display a linear -sweep- of the entire accelerator pedal range, and should not exhibit any voltage drop or signal break. If the feedback signal is not within the specified range, additional diagnosis is required in order to determine the proper function of the APP Sensor, or if a fault exists in any related sub-systems.
The APP Sensor provides a linear input signal (See Figure 1) to the Powertrain Control Module (PCM), which is used to monitor the throttle position. The APP Sensor monitors the entire range of throttle opening from 0.5 volts DC (0%) 4.5 volts DC (100%). In modern drive-by-wire throttle control systems, the APP Sensor provides data to the PCM in order to calculate the desired throttle position, in addition to air-fuel mixture, ignition timing, fuel injector pulse width, and transmission/transaxle gear position.
The APP Sensor utilizes positive coefficient logic: as the accelerator position is increased, the voltage is increased.Connection & Wiring Diagnosis
Refer to the Electrical Wiring Diagram for component and connector locations, connector views, and circuit-specific information.
Many intermittent open or short circuits may be caused by wiring harness and connector movement due to vibration, engine torque, bumps and rough pavement, etc.
Test the wiring harness and connectors by performing the following tests:
Move the related connectors and wiring while monitoring the appropriate scan tool data.
Test the connector terminal pins and/or wiring by performing the following tests:
Inspect for incorrect mating of the connector halves, or terminals not fully seated in the connector body.